when you sublet an apartment...?

Question

what does this mean?

Answer 1

If you are a tenant renting an apartment and then lease it to someone else, you are subletting the apartment. You are still liable for your lease. So if the subletter doesn't pay, the landlord can still go after you. Some leases don't allow subletting, so you would have to review your lease agreement before doing something like this.

Answer 2

You become a landlord and a tenant at the same time.